Fusible link



Dec. 1, 1931. R H RUSSELL 1,834,319

FUSIBLE LINK Filed May 9, 1950 Patented Dec. 1, 1931 PATE' *oFFICE ROBERT E. RUSSELL, F WORCESTER, MASSACHUSETTS, ASSIGNOR To RooKWoon f SPRINKLER ooMrANY. or MASSACHUSETTS, AcoRroRATIon or'MnssAcrrUsETTS USFUSIB'IFIE LINK p I Application filed. May 9, This invention relates to a fusible link de signed for use inconnection wlthsprinkler's,

fire doors and other heat-controlled struc t'ures. invention possesses particular. ad-.

vantageswhen used in sprinkler heads as will be hereinafter pointed'out;

It is the general object of my invention to provide a fusible link of an improved construction so designed that it will be'more quickly responsive to a rise in temperature.

A further object is to provide a fusible link in which the fusible metal is so disposed that accidental release ofthe sprinkler controlled I thereby is rendered substantially impossible.

My invention further relates'to arrangements and combinations of parts whlch Wlll. be hereinafter descrlbed and more particularly pointed out in the appended claims.

A preferred form of theinventionis shown 'in the drawings, in which Fig.1 is .a side elevation of a sprinkler head having my improved fusible link mounted thereon; I V

Fig. 2 is a side elevation of the fusible link, looking in the direction of the arrow 2 in Fig. 1;

Figs. 3, 4 and 5 are perspective views of the different parts comprising my improved link;

Fig. 6 is a sectional elevation of the fusible link; and

Fig. 7 is a sectional bottom view, taken along the line 77 in Fig. 6. r

Referring to the drawings, I have shown a sprinkler head of a commercial form-which comprises a threaded support 10 halving an, open frame structure 11 projecting upwardly therefrom. A cap 12 closes the opening v through the support 10 and the cap 12 is held firmly seated by lockinglevers 13pressed downward by an adjusting screw 14. The

outer ends of the levers 13 are provided with hooklike projections 15' which are normally held from separation by a fusible link to be described.

My improved fusible link comprises tension members 20 and 21 anda locking or're-" tainlng member 22. Each tension member is provided with an open1ng23, preferably reenforced by a grommet 24, these openings be 1930. Serial 1%; 451,160.

r of the levers 13.

'The'tension member 20 is provided with'a provided'with a corresponding opening 26; The openings 25 and 26' are positioned'in alignment when the'linkis assembled. z 1 The tenslon member 21 is also provided portion 34. The locking member 22 is pro-" vided with anend projection 36' and with offset lugs or projections end of said member.

When the parts are assembled, as indicated i'n Fig. '6,*the locking member 22 is disposed ing adapted to receive the hook-shaped ends rectangularopening 25 and the member 21 isat the opposite within and beneath the projecting hood 30, a

with the end projection 36 extending through the openlngs 25 and 26 in thetension members20 and 21. The offsetlugs 37 are dis posed adjacent the recessed endportion 34 of. the hood 30 but are of such height thatthei locking'member cannot enter within the recessed portion 34. 1

Afterthe parts are thus assembled, the adjacent faces of the tensionmembers 20'and I 21 are soldered or sweated together with a.

low melting solder and this solder is also disposed between the locking member 22 and the hood 30 and also within and around the recessed end 34'of the hood 30 and the offset lugs 37 of the locking member 22. Solder is also disposed inthe openings 25 and 26' around the end 36'of the locking member 22.

i It will be seen that the solder around the recessed end 34 and the outer end of the'lock ing member "22 and its lugs 37 is so disposed that the solder is Shear and will strong-v 1y resist the swinging movement of the locking member: 22 necessary to release the tension member 20 from the tension member 21. Thisdisposal of the solder in shear, together 'with'the long leverage at which the s'olderf acts on the locking'member, forms a very secure means for holding the locking member in positionuntil a rise'in temperature which will definitely soften. or "melt the solder.

The-opening 26 in the member 21 is continned into the top surface of the hood 30, as indicated at 40, so that the locking member may be free to swing when the solder melts and the locking member is released.

hen my improved fusible link is in use, the hood 30 and locking member 22 project into an opening between the locking levers 13, as indicated in Fig. 1, and are thus effectively protected from accidental damage. Furthermore, when a fire occurs beneath. a sprinkler equipped with my link, the hood 30, which is disposed in the path of the up wardly moving hot gases, banks them so that the retaining solder. is. more quickly melted.

Another advantage of the hood is that it it acts as an umbrella to protect thefusible solder from gathering dirt or dust which might tend to insulate it and soretard its melting.

Having thus described my invention and the advantages thereof, '1 do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is 1. A fusible link comprising two adj acenttension members and a locking member, one of said tension members having a hood projecting laterally therefrom, and said locking member being disposed within and beneath said hood and being secured in locking position by low-melting fusible material connecting a portion of said locking member to said hood.

2. A fusible link comprisingtwo acent tension members and a locking member,,saidtension members having aligned openings tl rough, which a portion of said locking member extends, and one of said tension members having a laterally projecting portion to and beneath which said locking memberis secured by a portion of low-melting fusible material.

v A fusible link comprising two adjacent tension members and a locking member, said tension members having aligned openings,

and one of said tension membershaving a hood projecting laterally therefrom, to-and beneath which said locking member is secured by low-melting fusible material connecting a portion of said locking member to said hood, with one end of said locking member extending through said aligned openings.

4:. A fusible link comprising two adjacent tension members and a locking member, said tension members having aligned openings, and one of said tension members having a hood projecting laterally therefrom, to and beneath which said locking member is secured by. low-melting material in shear, with one hood.

7, The combination in afusiblelink as setforth in claim 4, in which the projecting hood has its outer end recessed to receive a portion of"said'lowmelting material, and in which said locking member is provided with offset projections of such length as to engage the recessed end ofsaid hood and thereby exclude the end of said locking,memberffromfsaid,

recessed end,

Intest1monywhereof I have hereunto af fixed my slgnature.

' ROBERT H. RUSSELL.

end of said locking member extending througlrsaid aligned openings. 7

5. Thecombmation in a fusible link as set forth 1-11 cla m 4, in which the projecting 

